RHSA-2017:3470 - Security Advisory

Topic

An update for qemu-kvm-rhev is now available for Red Hat OpenStack Platform 9.0 (Mitaka).

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm-rhev packages provide the user-space component for running virtual machines that use KVM in environments managed by Red Hat products.

Security Fix(es):

• An assertion-failure flaw was found in the Network Block Device (NBD) server's initial connection negotiation, where the I/O coroutine was undefined. This could crash the qemu-nbd server if a client sent unexpected data during connection negotiation. A remote user or process could use this flaw to crash the qemu-nbd server resulting in denial of service. (CVE-2017-7539)
• Quick Emulator (QEMU) built with the Network Block Device (NBD) Server support is vulnerable to a crash via a SIGPIPE signal. The crash can occur if a client aborts a connection due to any failure during negotiation or read operation. A remote user/process could use this flaw to crash the qemu-nbd server resulting in a Denial of Service (DoS). (CVE-2017-10664)
• Quick Emulator (QEMU), compiled with qemu_map_ram_ptr to access guests' RAM block area, is vulnerable to an OOB r/w access issue. The crash can occur if a privileged user inside a guest conducts certain DMA operations, resulting in a DoS. (CVE-2017-11334)
• Quick Emulator (QEMU), compiled with the PC System Emulator with multiboot feature support, is vulnerable to an OOB r/w memory access issue. The issue could occur due to an integer overflow while loading a kernel image during a guest boot. A user or process could use this flaw to potentially achieve arbitrary code execution on a host. (CVE-2017-14167)
• Quick emulator (QEMU), compiled with the Cirrus CLGD 54xx VGA Emulator support, is vulnerable to an OOB write access issue. The issue could occur while writing to VGA memory via mode4and5 write functions. A privileged user inside guest could use this flaw to crash the QEMU process resulting in Denial of Serivce (DoS). (CVE-2017-15289)

Red Hat would like to thank Alex for reporting CVE-2017-11334; Thomas Garnier (Google.com) for reporting CVE-2017-14167; and Guoxiang Niu (Huawei.com) for reporting CVE-2017-15289.

Bug Fix(es):

• Hot-unplugging Virtual Function I/O (VFIO) devices previously failed when performed after hot-unplugging a vhost network device. This update fixes the underlying code, and the VFIO device is unplugged correctly in the described circumstances. (BZ#1498140)

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.

Affected Products

• Red Hat OpenStack 9 x86_64

Fixes

• BZ - 1466190 - CVE-2017-10664 Qemu: qemu-nbd: server breaks with SIGPIPE upon client abort
• BZ - 1471638 - CVE-2017-11334 Qemu: exec: oob access during dma operation
• BZ - 1473622 - CVE-2017-7539 Qemu: qemu-nbd crashes due to undefined I/O coroutine
• BZ - 1489375 - CVE-2017-14167 Qemu: i386: multiboot OOB access while loading kernel image
• BZ - 1498140 - Hot-unplugging a vhost network device leaks references to VFIOPCIDevice's [OSP 9]
• BZ - 1501290 - CVE-2017-15289 Qemu: cirrus: OOB access issue in mode4and5 write functions

CVEs

• CVE-2017-7539
• CVE-2017-10664
• CVE-2017-11334
• CVE-2017-14167
• CVE-2017-15289

References

• https://access.redhat.com/security/updates/classification/#moderate